The present invention relates to a crane monitoring system, and more particularly to a visual system for monitoring outriggers, other crane components and an area surrounding the crane.
Mobile cranes typically include a carrier unit in the form of a transport chassis and a superstructure unit having an extendable boom. The superstructure unit is typically rotatable upon the carrier unit. In transport the crane is supported by the carrier unit on its axles and tires.
At times, the mobile crane needs to be stabilized beyond what can be provided while resting on the tires and axles of the transport chassis. In order to provide stability and support of the crane during lifting operations, it is well known to provide the carrier unit with an outrigger system. An outrigger system will normally include at least two (often four or more) outriggers for supporting the mobile crane. The outrigger system may include telescoping outrigger beams with outrigger jacks and outrigger pads for supporting the mobile crane when the crane is located in a position at which it will perform lifting tasks.
Utilizing the telescoping outrigger beams, the outrigger pads may be extended to lateral locations at which they will provide a stabilizing base for the crane. Once positioned, the outrigger jacks are extended, lowering the outrigger pads into contact with the ground in order to support and stabilize the carrier unit and the superstructure unit. The outrigger jacks may be extended sufficiently, if desired, so as to support the crane in a manner such that the tires are elevated above the ground.
Historically, a crane operator would determine the degree to which the telescoping outrigger beams should be extended to properly stabilize a crane, and manually inspect the outriggers to determine if the outrigger pads were in position and contacting the ground. More recently, outrigger monitoring systems have been developed to assist an operator. These systems typically rely on measurement devices such as string potentiometers, proximity sensors, laser sensors, and other distance sensors. While each of the aforementioned systems is able to determine the extension of the outriggers, it would be beneficial to develop a low cost, reliable system to visually monitor the outriggers, including the extension of the outriggers.